第一种常见的实现算法是基于Ring的AllReduce，英伟达的NCCL通信库采用了这种算法，该算法每次跟相邻的两个节点进行通信，每次通信数据总量的N分之一，过程如下图。Ring AllReduce算法图示 该算法的优点是实现简单，能充分利用每个节点的上行和下行带宽；缺点是通信延迟随着节点数线性增加，特别是对于小包延迟增加比较
为了解决这个问题,引入了一种GPU卡之间的通信方式的优化算法,就是Ring All-Reuce, 它是高性能领域中的一个经典算法,并不是为了深度学习而生。 它的优点是通信量是恒定的,不随GPU数量的增加而增长。这个算法分两个步骤,第一步是scatter-reduce, 然后是allgather。scatter-reduce操作将GPU交换数据,是的每个GPU可得...
tree_alltree_reducetree_reduce(with init)tree_transpose(Not Implemented) jax pytree1.47 µs ± 37 ns1.88 µs ± 27.2 ns1.91 µs ± 47.4 ns10 µs ± 117 ns--- This is the comparison between dm-tree, jax-libtree and us, withflattenandmappingoperations (lower value means less ti...
tree_alltree_reducetree_reduce(with init)tree_transpose(Not Implemented) jax pytree1.47 µs ± 37 ns1.88 µs ± 27.2 ns1.91 µs ± 47.4 ns10 µs ± 117 ns--- This is the comparison between dm-tree, jax-libtree and us, withflattenandmappingoperations (lower value means less ti...
species’ IUCN Red List statuses into three conservation status groups to (1) reduce potential inconsistencies due to data accuracy from rates of recent change, (2) reduce data and knowledge dependencies among species, and (3) facilitate interpretation of (in)consistencies between rates of recent ...
of the mean of diversity metrics calculated across the 200 iterations of subsamples taken with replacement (to reduce the degree to which confidence intervals were conditional on the sample). For point estimates, all datasets were compared at the common sample size of the Southeast Asia dataset (...
(1)Map-Reduce Framework Counters (2)File System Counters Counters (3)Job Counters (4)File Input/Output Format Counters 1.3 自定义计数器# 虽然Hadoop 内置的计数器比较全面,给作业运行过程的监控带了方便,但是对于一些业务中的特定要求(统计过程中对某种情况发生进行计数统计)MapReduce 还是提供了用户编写自定...
You can grow shallower trees to reduce model complexity or computation time. To control the depth of trees, use the 'MaxNumSplits', 'MinLeafSize', or 'MinParentSize' name-value pair arguments. Load the carsmall data set. Consider Displacement, Horsepower, and Weight as predictors of the ...
MapReduce 是一个分布式运算程序的编程框架,是用户开发“基于 Hadoop 的数据分析应用”的核心框架。 MapReduce 核心功能是将用户编写的业务逻辑代码和自带默认组件整合成一个完整的分布式运算程序,并发运行在一个 Hadoop 集群上。 1.1 引入# MapReduce 的思想核心是“先分再合,分而治之”。
决策树(decision tree)是一种依托于策略抉择而建立起来的树。机器学习中,决策树是一个预测模型;他代表的是对象属性与对象值之间的一种映射关系。 树中每个节点表示某个对象,而每个分叉路径则代表的某个可能的属性值,从根节点到叶节点所经历的路径对应一个判定测试序列。决策树可以是二叉树或非二叉树,也可以把他看...